My new 600ex-rt seems to be 300K higher in color temperature (bluer)

[PhotoCat]

Hi all!

I am continuing to test my new 600ex-rt.
Flash Setting at full power 1/1, 105mm direct flash firing at a piece of white paper.
Using ML v2.3 RGB spot metering, I needed to WB my camera to 6300K in order to
get all 3 RGB values to match.

This tells me that my 600 is about 300K bluer than a "standard" flash, which is at 6000K.

My real life shooting has confirmed my test. I needed to dial K about 300K higher than my
usual setting to get the correct skin tone. i.e. when I gel with CTS I used to need 3700K but now
I need to go to 4000K.

Out of curiosity, I pulled out a mint Nikon SB-80DX and tried that too. It is spot on at 6000K.
BTW, camera used was 5D2.

So I am just wondering if others r seeing this too?

Thanks!

 

[Jim Saunders]

Pardon my innocence, but is the 5% difference not academic?

Jim

 

[PhotoCat]

Pardon my innocence, but is the 5% difference not academic?

Jim

Hi Jim,
I agree 5% by number is probably quite insignificant but 300K in color temperature
is very noticeable IMHO. I noticed the blueness right away when I shot with it in the same venue.

I guess I can live with the 300K offset adjustment but I just wanted to make sure this 300K offset
is not a symptom of a more serious manufacturing defect of my new unit. That's why I am checking
if others r seeing the same phenomenon.

More tests were done with different power levels of the 600ex-rt and results as follows:

1/1 6300K
1/2 6500K
1/4 6600K
1/8 6600K

 

[Jim Saunders]

Weird. I'll try mine, hang on a few minutes.

Jim

 

[tpatana]

300 is easily noticeable when you compare side-by-side, but not so much if you just pick random photo and it's off that much. Also depends plenty on the photo.

 

[Drizzt321]

Probably has to do with the differences in power from partial to full. Contact Canon and see if this is a normal deviation from spec, or if there's maybe a faulty capacitor or something that's causing it to not give quite enough power at full power to the flash tube.

 

[Jim Saunders]

I shot my WhiBal card and got 5850, 5900 and 6100; That was each light on well-charged AAs and the same setup. 6300 seems a little high but as long as it is consistent then I don't think it is worth much trouble.

Jim

 

[PhotoCat]

I shot my WhiBal card and got 5850, 5900 and 6100; That was each light on well-charged AAs and the same setup. 6300 seems a little high but as long as it is consistent then I don't think it is worth much trouble.

Jim

Thanks Jim for helping out. I am guessing your 3 numbers are for power 1/1, 1/2 and 1/4 respectively.
The change in color temp is 250K from 1/1 to 1/4. Mine is 300K.
Looks a little better than mine I guess. This tells me 600ex-rt's color temp does vary considerably with power level.
Also the absolute color temperature value does have manufacturing variations
as much as a few hundred k's.

Just tried my old 580exii again just to compare:

1/1 6200
1/2 6300
1/4 6300
1/8 6300

Color temp on 580exii seems a lot tighter with respect to power.

Thanks to all who had replied!

 

[Jim Saunders]

Those numbers are for each of my three lights fired in ETTL at a piece of paper on the wall, with white balance drawn from the white panel on my WhiBal card using the tool in LR5; I should have specified. If you want I can try each of them at different power settings.

Jim

 

[PhotoCat]

Those numbers are for each of my three lights fired in ETTL at a piece of paper on the wall, with white balance drawn from the white panel on my WhiBal card using the tool in LR5; I should have specified. If you want I can try each of them at different power settings.

Jim

oic... thanks Jim for all the help! I think I have a bigger problem than that now...
My 600 is vy voltage sensitive with regard to recycling time.
Freshly charged Eneloop AA batteries give a recycling time of 2.4S when an eneloop
charged just 2 days ago gives > 3.2S! I think this is unacceptable and I am going to exchange my 600ex-rt.
Probably the color temp thing is related.

Thanks all for helping out! John